Method for forming semiconductor structure

Abstract

Methods for forming a semiconductor structure are provided. In one form, a method includes: providing a base; forming an initial pattern layer on the base; and performing atomic layer etching processing on a sidewall of the initial pattern layer one or more times to form a pattern layer, where the atomic layer etching processing includes: forming an organic layer on the sidewall of the initial pattern layer; and removing the organic layer. Generally, bond energy between an atom on an outermost surface of the sidewall of the initial pattern layer and an atom at an inner layer is less than bond energy between the atom at the inner layer. The organic layer usually includes an element that may react with the sidewall of the initial pattern layer, further reducing the bond energy between the atom on the outermost surface of the sidewall of the initial pattern layer and the atom at the inner layer. During removal of the organic layer, the atom on the outermost surface of the sidewall of the initial pattern layer may be peeled off. In this way, after a plurality of times of atomic layer etching processing, a protruding region on the sidewall of the initial pattern layer is flattened. Accordingly, the sidewall of the formed pattern layer has a relatively small roughness, so that electrical performance of the semiconductor structure can be improved.